used exhaust if possible.
test pipes although i dont know much about them look to be promising from Turner. I need to have a look into that for my own car.
trade someone rims plus cash for their zcps =) . powdercoat them. or if you have stock 19's, i'd powder coat them, run 18mm MS spacers up front and a 15mm in the rear. a nice drop with eibachs and i'd recommend Eibachs for a drop especially if you want to track your car. and notice im dumped on RD sport. I say this cause if you plan on tracking your car, stock suspension is the best, next to coilovers. My car w/ the RD's has more bodyroll with the RD's on then it ever did w/ the stocks. And dont listen to what others mislead you to, i did it soley for visual purposes because the eibachs just didn't cut it for me, the drop wasn't aggressive at all, and I would never put an H&R labeled product on my car. My car handles fine, but im super crazy when it comes to my car and everyday i leave my house i have a nice little canyon stretch so I know how my car feels. Definitely feel like my stock setup would destroy my RD's around a track. So I'd recommend the eibachs because its a conservative drop, shouldn't affect the overall driving characteristics of the car quite like H&R's and RD sport. The lower you drop with springs, the worse these cars will handle COMPARED with stocks. if you drop w/ something lower than eibach than get 15mm spacers and 12mm spacers. Another thing about eibachs is many forum members love them, which is also a great sign and many track their cars with them.

A replica front lip.. Keep in mind, all these aftermarket ones are technically replicas.. lol idk what dubbed them as authentic over the years, perhaps its the many fan boy members on these bimmer sites. fitment is good enough on many such as JL motoring and at the end of the day your probably going to mess it up within the first month of having it. but i have to admit, that challenge front looks like pure perfection. look at that fitment and design is perfect

Change out your side grills and lights
Painted reflectors, and only from IND.. cause their the best. PERIOD
Matte black grills
Matte black M emblem
Black M plate frame from amazon